Method and catalyst composition for producing aromatic carbonates

ABSTRACT

The present invention provides a method and catalyst composition for carbonylating aromatic hydroxy compounds, comprising the step of contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst composition comprising an effective amount of at least one Group 8, 9, or 10 metal source, an effective amount of a combination of inorganic co-catalysts comprising at least one Group 4 metal source and at least one Group II metal source, an effective amount of at least one salt co-catalyst with an anion selected from the group consisting of carboxylate, benzoate, acetate, sulfate, and nitrate, wherein the carbonylation catalyst composition is free of a halide source.

BACKGROUND OF THE INVENTION

[0001] The present invention is directed to a catalyst composition andmethod for producing aromatic carbonates through the carbonylation ofaromatic hydroxy compounds.

[0002] Aromatic carbonates find utility, inter alia, as intermediates inthe preparation of polycarbonates. For example, a popular method ofpolycarbonate preparation is the melt transesterification of aromaticcarbonates with bisphenols. Various methods for preparing aromaticcarbonates have been previously described in the literature and utilizedby industry. A method that has enjoyed substantial popularity in theliterature involves the direct carbonylation of aromatic hydroxycompounds with carbon monoxide and oxygen catalyzed by at least oneGroup 8, 9 or 10 metal source. Further refinements to the carbonylationcatalyst composition include the identification of co-catalysts.

[0003] The utility of the carbonylation process is strongly dependent onthe number of moles of desired aromatic carbonate produced per mole ofGroup 8, 9, or 10 metal utilized (i.e. “catalyst turnover number or‘TON’”). Consequently, much work has been directed to the identificationof efficacious catalyst compositions that increase the catalyst turnovernumber.

[0004] Carbonylation catalyst literature lauds the effectiveness ofhalide salts, particularly bromide salts, in catalyst compositions forimproving catalyst TON's. While it is true that catalyst compositionsthat contain halide salts have historically exhibited high activity,there are drawbacks to using halide in a carbonylation reaction. Forexample, when used to carbonylate phenol, bromide anions are consumed inthe process, forming undesirable brominated byproducts, such as 2- and4-bromophenols and bromodiphenylcarbonate.

[0005] It would be desirable to identify catalyst compositions thatwould minimize consumption of components or perhaps that would omitcomponents such as halide. It would also be desirable to increaseselectivity toward the desired carbonate product and minimizingformation of undesirable halogenated byproducts.

[0006] As the demand for high performance plastics has continued togrow, new and improved methods of providing product are needed to supplythe market. Consequently, a long felt, yet unsatisfied need exists fornew and improved methods and catalyst compositions for producingaromatic carbonates and the like.

SUMMARY OF THE INVENTION

[0007] Accordingly, the present invention is directed to a method andcatalyst composition for producing aromatic carbonates. In oneembodiment, the present invention provides a method for carbonylatingaromatic hydroxy compounds, comprising the step of contacting at leastone aromatic hydroxy compound with oxygen and carbon monoxide in thepresence of a carbonylation catalyst composition comprising an effectiveamount of at least one Group 8, 9, or 10 metal source, an effectiveamount of a combination of inorganic co-catalysts (IOCC) comprising atleast one Group 4 metal source and at least one Group 11 metal source,an effective amount of at least one salt co-catalyst with an anionselected from the group consisting of carboxylate, benzoate, acetate,sulfate, and nitrate, wherein the carbonylation catalyst composition isfree of a halide source.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0008] The present invention is directed to a carbonylation method andcatalyst composition for producing aromatic carbonates. The constituentsof the carbonylation catalyst composition are defined as “components”irrespective of whether a reaction between said constituents occursbefore or during the carbonylation reaction. Thus, the catalystcomposition includes the components and any reaction products thereof.In one embodiment, the method includes the step of contacting at leastone aromatic hydroxy compound with oxygen and carbon monoxide in thepresence of a carbonylation catalyst composition that comprises aneffective amount of at least one Group 8, 9, or 10 metal source, acombination of inorganic co-catalysts (IOCC) comprising effectiveamounts of at least one Group 4 metal source and at least one Group 11metal source, and an effective amount of at least one salt co-catalystwith an anion selected from the group consisting of carboxylate,benzoate, acetate, sulfate, and nitrate, wherein the carbonylationcatalyst composition is free of a halide source. Unless otherwise noted,the term “effective amount,” as used herein, includes that amount of asubstance capable of yielding the desired aromatic carbonate, orincludes that amount of a substance that increases the selectivity ofany one of the starting reagents (e.g. oxygen, carbon monoxide, andaromatic hydroxy compound) towards the desired aromatic carbonate.

[0009] In another embodiment, the method includes the step of contactingat least one aromatic hydroxy compound with oxygen and carbon monoxidein the presence of a carbonylation catalyst composition that comprisesan effective amount of at least one Group 8, 9, or 10 metal source, acombination of inorganic co-catalysts (IOCC) comprising effectiveamounts of at least one Group 4 metal source and at least one Group 11metal source, an effective amount of at least one salt co-catalyst withan anion selected from the group consisting of carboxylate, benzoate,acetate, sulfate, and nitrate, and an effective amount of base, whereinthe carbonylation catalyst composition is free of a halide source.

[0010] In yet another embodiment, the method includes the step ofcontacting at least one aromatic hydroxy compound with oxygen and carbonmonoxide in the presence of a carbonylation catalyst composition thatcomprises an effective amount of at least one Group 8, 9, or 10 metalsource, a combination of inorganic co-catalysts (IOCC) comprisingeffective amounts of at least one Group 4 metal source and at least oneGroup 11 metal source, an effective amount of at least one saltco-catalyst with an anion selected from the group consisting ofcarboxylate, benzoate, acetate, sulfate, and nitrate, and an effectiveamount of an activating organic solvent, wherein the carbonylationcatalyst composition is free of a halide source.

[0011] In yet another embodiment the method includes the step ofcontacting at least one aromatic hydroxy compound with oxygen and carbonmonoxide in the presence of a carbonylation catalyst composition thatcomprises an effective amount of at least one Group 8, 9, or 10 metalsource, a combination of inorganic co-catalysts (IOCC) comprisingeffective amounts of at least one Group 4 metal source and at least oneGroup 11 metal source, an effective amount of at least one saltco-catalyst with an anion selected from the group consisting ofcarboxylate, benzoate, acetate, sulfate, and nitrate, an effectiveamount of an activating organic solvent, and an effective amount of atleast one base, wherein the carbonylation catalyst composition is freeof a halide source.

[0012] Any aromatic hydroxy compound, which is convertible to acarbonate ester, is suitable in the present invention. For example,suitable aromatic hydroxy compounds include, but are not limited to,monocyclic, polycyclic or fused polycyclic aromatic monohydroxy orpolyhydroxy compounds having from about 6 to about 30, and preferablyfrom about 6 to about 15 carbon atoms. Illustrative examples include,but are not limited to, phenol, alkylphenols, alkoxyphenols, bisphenols,biphenols, and salicylic acid derivates such as methyl salicylate.

[0013] The carbonylation catalyst composition contains at least onecatalyst component selected from Group 8, 9 or 10 metal sources. TypicalGroup 8, 9 or 10 metal sources include ruthenium sources, rhodiumsources, palladium sources, osmium sources, iridium sources, platinumsources, and mixtures thereof. The quantity of the Group 8, 9, or 10metal source is not limited in the process of the present invention. Theamount employed should be about 1 gram of Group 8, 9, or 10 metal per100 grams to 1,000,000 grams of aromatic hydroxy compound (i.e. about 1part per million (ppm) to about 10,000 ppm of Group 8, 9, or 10 metal).For example, about 1 ppm to about 1000 ppm of Group 8, 9, or 10 metal issuitable. In one embodiment of the present invention about 1 ppm toabout 30 ppm of Group 8, 9, or 10 metal is used. A typical Group 8, 9,or 10 metal source is a palladium source. The palladium source used istypically in the Pd (II) oxidation state at the beginning of thereaction. Alternatively, a palladium compound in either the Pd(O) orPd(IV) oxidation states can be used. As used herein, the term “compound”includes inorganic, coordination and organometallic complex compounds.The compounds are typically neutral, cationic, or anionic, depending onthe charges carried by the central atom and the coordinated ligands.Other common names for these compounds include complex ions (ifelectrically charged), Werner complexes, and coordination complexes. AGroup 8, 9, or 10 metal source can be employed in a homogeneous formthat is substantially soluble in the reaction media or in aheterogeneous form which is substantially insoluble in the reactionmedia, including, supported or polymer bound species. Examples ofsuitable palladium sources include, but are not limited to, palladiumsponge, palladium black, palladium deposited on carbon, palladiumdeposited on alumina, palladium deposited on silica, palladium sulfates,palladium nitrates, palladium carboxylates, palladium oxides, palladiumacetates, palladium salts of β-diketones, palladium salts ofβ-ketoesters, and palladium compounds containing any of the followingligands: carbon monoxide, amine, nitrite, nitrite, isonitrile,phosphine, phosphite, phosphate, alkoxide, alkyl, aryl, silyl or olefin.In one embodiment palladium(II) acetate is used. In another embodimentpalladium(II) 2,4-pentanedionate is used.

[0014] The carbonylation catalyst composition in the present inventionfurther comprises a combination of inorganic co-catalysts comprisingeffective amounts of at least one Group 4 metal source, and at least oneGroup 11 metal source. As used herein, the term “inorganic co-catalyst”(IOCC) includes any catalyst component that contains a metal element,which is present in the catalyst composition in addition to the Group 8,9 or 10 metal source. The Group 4 metal source is at least one selectedfrom the group consisting of zirconium, hafnium, and titanium. The Group11 metal source is at least one selected from the group consisting ofsilver, gold and copper. Suitable forms of Group 4 and Group 11 IOCC'sinclude, but are not limited to, elemental metals, salts, metalcompounds in stable oxidation states, and precursors thereof which formcatalytically active metal species under the reaction conditions. Thecompounds are typically neutral, cationic, or anionic, depending on thecharges carried by the central atom and the coordinated ligands.Illustrative examples of Group 4 and Group 11 IOCC's include, but arenot limited to, oxides, carboxylates, acetates, salts of β-diketones,salts of β-ketoesters, nitrates, and compounds containing any of thefollowing ligands: carbon monoxide, amine, nitrite, nitrite, isonitrile,cyanide, phosphine, phosphite, phosphate, alkoxide, alkyl, aryl, silylor olefin. The IOCC's are typically initially soluble in the reactionmixture, and typically remain soluble or become at least partiallyinsoluble during the course of the reaction, or they are typicallyinitially insoluble in the reaction mixture, and remain either insolubleor become at least partially soluble during the course of the reaction.Alternatively, the IOCC's are typically supported or polymer-bound witha variety of support media, including but not limited to carbon,alumina, silica, and zeolites.

[0015] In one embodiment the Group 4 metal is titanium. Illustrativeexamples of titanium sources include, but are not limited to, titanyloxides, titanium alkoxides, titanium aryloxides, titanium nitrates,titanium carboxylates, and titanium sulfates. Additional examples oftitanium sources include titanium compounds containing any one of thefollowing ligands: carbon monoxide, amine, nitrite, nitrate nitrite,isonitrile, cyanide, phosphine, phosphite, phosphate, alkoxide, alkyl,aryl, silyl, olefin, β-diketone, or β-ketoester. In one embodiment thetitanium sources is titanium(IV) oxide 2,4-pentanedionate. Mixtures oftitanium compounds are also suitable.

[0016] In one embodiment the Group 11 metal is copper. Examples ofcopper sources include, but are not limited to, copper oxides, copperalkoxides, copper aryloxides, copper nitrate, copper carboxylates,copper sulfate, and copper compounds containing any one of the followingligands: carbon monoxide, amine, nitrite, nitrile, isonitrile, cyanide,phosphine, phosphite, phosphate, alkoxide, alkyl, aryl, silyl, olefin,β-diketone, or β-ketoester. In one embodiment the copper compound iscopper(II) 2,4-pentanedionate. Mixtures of copper compounds are alsosuitable.

[0017] In addition to the inorganic components of the carbonylationcatalyst composition in the present invention, at least one saltco-catalyst with an anion selected from the group consisting ofcarboxylate, benzoate, acetate, sulfate, and nitrate is also present.Examples of suitable organic co-catalyst salts include, but are notlimited to, salts that contain a cation selected from the groupconsisting of alkali metal cations, alkaline-earth metal cations,guanidinium cations, and onium cations. For example, suitable organicsalt co-catalysts include, but are not limited to, alkylammoniumcarboxylates (e.g. tetrabutylammonium benzoate), alkali metal acetates(e.g. sodium acetate), alkylammonium sulfates (e.g. tetrabutylammoniumsulfate), and alkali metal nitrates (e.g. sodium nitrate).

[0018] The salt co-catalyst components in the carbonylation catalystcomposition of the present invention can also be produced in situ. Forexample, the desired salt co-catalyst component can be formed by addingthe appropriate acid-base combination to the reaction mixture to producethe desired salt co-catalyst in situ. Therefore, addition of alkalimetal bases or alkaline-earth metal bases or amines in combination withthe conjugate acids of benzoate, acetate, sulfate, or nitrate anionswill produce the desired components in situ. For example, in the casewhere the desired salt co-catalyst component is sodium acetate, additionof sodium hydroxide and acetic acid to the reaction mixture will producethe desired sodium acetate in situ. Alternatively, in the case where thedesired salt co-catalyst is an alkylammonium benzoate, such astetrabutylammonium benzoate, addition of tributyl amine and benzoic acidto the reaction mixture will produce tributylammonium benzoate in situ,which is a functional equivalent of tetrabutylammonium benzoate.

[0019] The carbonylation catalyst composition typically includes aneffective amount of at least one activating organic solvent. Forexample, activating organic solvents include polyethers (e.g. compoundscontaining two or more C—O—C linkages). The polyether used is typicallyfree from hydroxy groups to maximize its desired activity and avoidcompetition with the aromatic hydroxy compound in the carbonylationreaction. Typical polyethers contain two or more (O—C—C) units. Thepolyether is typically an aliphatic or mixed aliphatic-aromatic. As usedin the identification of the polyether, the term “aliphatic” refers tothe structures of hydrocarbon groups within the molecule, not to theoverall structure of the molecule. Thus, “aliphatic polyether” includesheterocyclic polyether molecules containing aliphatic groups withintheir molecular structure. Suitable aliphatic polyethers includediethylene glycol dialkyl ethers such as diethylene glycol dimethylether (hereinafter “diglyme”), triethylene glycol dialkyl ethers such astriethylene glycol dimethyl ether (hereinafter “triglyme”),tetraethylene glycol dialkyl ethers such as tetraethylene glycoldimethyl ether (hereinafter “tetraglyme”), polyethylene glycol dialkylethers such as polyethylene glycol dimethyl ether and crown ethers suchas 15-crown-5 (1,4,7,10,13-pentaoxacyclopentadecane) and 18-crown-6(1,4,7,10,13,16-hexaoxcyclooctadecane). Illustrative examples of mixedaliphatic-aromatic polyethers include diethylene glycol diphenyl etherand benzo-18-crown-6. Mixtures of polyethers are also suitable.

[0020] In alternative embodiments, the activating organic solvent can bea nitrile. Suitable nitrile solvents for the present method include C₂₋₈aliphatic or C₇₋₁₀ aromatic mononitriles or dinitriles. Illustrativemononitriles include acetonitrile, propionitrile, and benzonitrile.Illustrative dinitriles include succinonitrile, adiponitrile, andbenzodinitrile.

[0021] In further alternative embodiments, the activating organicsolvent can be a carboxylic acid amide. For example, fully substitutedamides (containing no NH groups including the amide nitrogen) aresuitable. Typically, aliphatic, aromatic or heterocyclic amides areused. Illustrative examples of amides include dimethylformamide,dimethylacetamide (hereinafter sometimes “DMA”), dimethylbenzamide andN-methylpyrrolidinone (NMP).

[0022] In yet another alternative embodiment, the activating organicsolvent is an aliphatic, aromatic or heterocyclic sulfone. Illustrativesulfones include dimethyl sulfone, diethyl sulfone, diphenyl sulfone andsulfolane (tetrahydrothiophene-1,1-dioxide).

[0023] It is noted that the function of the activating organic solventin the present invention is not that of an inert solvent. Rather, theactivating organic solvent is an active catalyst component that improvesthe yield of or selectivity toward the desired aromatic carbonate.Typically, about 1% to about 60% by volume based on the total volume ofaromatic hydroxy compound and activating organic solvent is used. In oneembodiment, about 1% to about 10% by volume based on the total volume ofaromatic hydroxy compound and activating organic solvent is used. Theamount of activating organic solvent typically depends to some extent onthe salt co-catalyst composition and the complexing ability of theactivating organic solvent employed. Crown ethers, for example, have avery high complexing tendency with alkali metal cations. For example,15-crown-5 complexes efficiently with sodium and 18-crown-6 withpotassium. Such compounds are used in amounts as low as an equimolaramount based on salt co-catalyst composition.

[0024] In one embodiment, at least one base is typically present incarbonylation catalyst composition of the present invention. Suitablebases include, but are not limited to, alkali metal, alkaline-earthmetal, guanidinium, or onium salts of basic oxides, hydroxides includingonium hydroxides, mono or polyalkoxides with linear or branched alkylchains having from about 1 to about 30 carbon atoms, aryloxidesincluding monocyclic, polycyclic or fused polycyclic aromaticmonohydroxy or polyhydroxy compounds having from about 6 to about 30,and preferably from about 6 to about 15 carbon atoms. Typical oniumcations contain organic residues which typically include C₁₋₂₀alkyl,C₆₋₁₀aryl, or alkyl-aryl combinations thereof. A second suitable classof bases includes tertiary amines with organic residues which containalkyl residues having from about 1 to about 20 carbon atoms, arylresidues having from about 6 to about 30, and preferably from about 6 toabout 15 carbon atoms, or alkyl-aryl combinations thereof. Typical basesinclude, but are not limited to, sodium hydroxide, lithium hydroxide,potassium hydroxide, tetraalkylammonium hydroxides (e.g.tetramethylammonium hydroxides, tetraethylammonium hydroxide,methyltributylammonium hydroxide and tetrabutylammonium hydroxide)sodium phenoxide, lithium phenoxide, potassium phenoxide, andtetraalkylammonium phenoxides (e.g. tetramethylammonium phenoxide,tetraethylammonium phenoxide, methyltributylammonium phenoxide andtetrabutylammonium phenoxide).

[0025] Typically, the molar ratio of the IOCC's relative to the Group 8,9, or 10 catalyst at the initiation of the reaction is between about 0.1mole and about 100 moles per mole of Group 8, 9, or 10 catalyst. In oneembodiment between about 1 mole and about 20 moles of each IOCC per moleof Group 8, 9, or 10 catalyst is used. In another embodiment, betweenabout 2 moles and about 15 moles of each IOCC per mole of Group 8, 9, or10 catalyst is used. For example, when the Group 8, 9, or 10 catalyst ispalladium, the molar ratio of titanium to palladium is typically betweenabout 2 moles and about 15 moles per mole of palladium at the initiationof the reaction, and the molar ratio of copper relative to palladium istypically between about 2 moles and about 15 moles per mole of palladiumat the initiation of the reaction.

[0026] The molar ratio of the salt co-catalyst relative to Group 8, 9,or 10 catalyst present in the carbonylation catalyst composition at theinitiation of the reaction is between about 0.1 mole and about 10000moles per mole of Group 8, 9, or 10 catalyst. In one embodiment themolar ratio of the salt co-catalyst relative to Group 8, 9, or 10catalyst is between about 1 mole and about 1000 moles. For example, whenthe Group 8, 9 or 10 catalyst is palladium, the molar ratio of the saltco-catalyst relative to palladium at the initiation of the reaction istypically between about 1 mole and about 600 moles per mole ofpalladium.

[0027] The molar ratio of the base relative to the Group 8, 9, or 10catalyst at the initiation of the reaction is typically between about0.1 mole and about 1000 moles of base per mole of the Group 8, 9, or 10catalyst. In one embodiment, the molar ratio of the base relative to theGroup 8, 9, or 10 catalyst is between about 1 mole and about 600 molesper mole of Group 8, 9, or 10 catalyst. For example, when the Group 8, 9or 10 catalyst is palladium the molar ratio of the base to palladium istypically between about 1 mole and about 400 moles per mole ofpalladium.

[0028] The carbonylation method can be carried out in a variety ofreactor systems including, but not limited to, stirred vessels,autoclaves and bubble columns, each of which is capable of beingoperated under batch-liquid/batch-gas reactor conditions (i.e.batch/batch), batch-liquid/continuous-gas reactor conditions (i.e.batch/flow or semi-continuous), or continuous-liquid/continuous-gasreactor conditions (i.e. flow/flow). In one embodiment two or morereactors are typically employed in a cascade. In one embodiment about 2to about 15 reactors are used. When a reactor cascade is used instead ofan individual reactor, the separate gas addition preferably proceeds insuch a way that the optimal gas concentrations are ensured in each ofthe reactors. Due in part to the low solubility of carbon monoxide andoxygen in organic aromatic hydroxy compounds, such as phenol, it ispreferable that each reactor vessel be pressurized. A total pressure inthe range up to about 35 megapascals (MPa) is used. In one embodimentthe reaction pressure is between about 0.5 MPa and about 14 MPa.

[0029] The reaction gases are typically reagent grade purity, andspecial care must be taken to ensure that no catalyst compositionpoisons are present as impurities in the gas sources. In one embodimentthe carbon monoxide and oxygen are introduced independently of eachother into the reactor vessel. In an alternative embodiment the carbonmonoxide and oxygen are introduced into the reactor vessel as a singlepremixed gas mixture comprising carbon monoxide and oxygen. Thecomposition of the reaction gases comprising carbon monoxide and oxygencan be varied in broad concentration ranges. For example the volumepercent oxygen in the gas mixtures can be up to about 0.1 volume % toabout 20 volume %. In one embodiment the volume % of oxygen in the gasmixture is between about 1% and about 9%. Gas sparging or mixing can beused to aid the reaction. Additional inert gases, such as nitrogen,helium, neon, argon, krypton, xenon, or any other gas which has nonegative effect on the carbonylation reaction can be added to thereactor vessel in order to dilute the carbon monoxide and oxygen gasmixture. For example, air is an acceptable substitute for pure oxygen.The concentration of inert gas in the reaction gas is typically up toabout 60 volume %. In one embodiment the volume % of inert gas is about0% to about 20% of the total gas volume.

[0030] Typical reaction temperatures are between about 50° C. and about150° C. In one embodiment the reaction temperature is between about 90°C. and about 110° C. Provisions are typically made for including adrying agent or a drying process step in the overall reaction method.Higher catalyst turnover numbers are typically obtained if water isremoved from the reaction mixture during the reaction.

[0031] The following examples are included to provide additionalguidance to those skilled in the art in practicing the claimedinvention. The examples provided are merely representative of the workthat contributes to the teaching of the present application.Accordingly, the following examples are not intended to limit theinvention, as defined in the appended claims, in any manner.

[0032] In the following examples, the aromatic carbonate produced isdiphenyl carbonate (DPC) and the Group 8, 9, or 10 metal utilized ispalladium. For convenience, the number of moles of DPC produced per moleof palladium charged to a reaction is referred to as the palladiumturnover number (Pd TON), and is used as an activity metric in thefollowing examples.

EXAMPLES 1-5

[0033] Carbonylation reaction were carried out in a glass reactionvessel containing 0.25 ppm concentration of palladium(II)2,4-pentanedionate in phenol, IOCC combinations in equivalents versuspalladium, various salt co-catalyst components in equivalents versuspalladium, and sodium hydroxide in equivalents versus palladium.Titanium was supplied as titanium(IV) oxide 2,4-pentanedionate andcopper as copper(II) 2,4-pentanedionate. The components were heated to100° C. for 3 hours in an atmosphere of approximately 6-7 mole % oxygenin carbon monoxide at about 11 megapascals. Amounts are in parts permillion (ppm) or equivalents (eq); TBA-Benz is tetrabutylammoniumbenzoate; NaOAc is sodium acetate; [TBA]₂-SO₄ is tetrabutylammoniumsulfate. Average results of multiple runs are given in Table 1. TABLE 1NaOH Pd Cu eq. Ti eq. Salt/ eq. vs. Pd Example ppm vs. Pd vs. Pd eq. vs.Pd Pd TON 1 25 12 6 TBA-Benz/400 200 1270 2 25 12 12 TBA-Benz/400 400641 3 25 12 12 NaOAc/400 400 98 4 25 12 6 NaOAc/400 200 340 5 25 12 12[TBA]₂-S0₄/400 400 1640

EXAMPLES 6-7

[0034] Carbonylation reaction mixtures comprised phenol solutions (about46 g) containing about 15 parts per million (ppm) palladium added aspalladium(II) 2,4-pentanedionate (about 0.0028 g), copper added ascopper(II) 2,4-pentanedionate 0.024 g), titanium added as titanium(IV)oxide 2,4-pentanedionate (about 0.48 g), sodium nitrate (about 0.187 g),tetraglyme (about 4.6 g), and optionally sodium hydroxide (about 0.055g). Reactions were carried out under batch-batch conditions in aHastelloy-C autoclave for about 3 hours at about 100° C. in a premixedgas mixture containing about 8.7 mole % oxygen in carbon monoxide at atotal pressure of about 10.3 MPa. Molecular sieves ({fraction (1/16)}″pellets, 3 Å, 30 g) were placed in a perforated Teflon basket mounted tothe stir shaft of the reactor. Amounts are in parts per million (ppm) orequivalents (eq). Reaction mixtures were analyzed by gas chromatography(GC). Results are shown in Table 2. TABLE 2 NaNO₃ NaOH Tetra- Pd Cu eq.Ti eq. eq. vs. eq. vs. glyme Pd Example ppm vs. Pd vs. Pd Pd Pd wt % TON6 15 10.7 21.4 256 0 9 2554 7 15 10.7 21.4 256 160 9 5373

[0035] It will be understood that each of the elements described above,or two or more together, can also find utility in applications differingfrom the types described herein. While the invention has beenillustrated and described as embodied in a method and catalystcomposition for producing aromatic carbonates, it is not intended to belimited to the details shown, since various modifications andsubstitutions can be made without departing in any way from the spiritof the present invention. For example, additional effective IOCCcompounds can be added to the reaction. As such, further modificationsand equivalents of the invention herein disclosed can occur to personsskilled in the art using no more than routine experimentation, and allsuch modifications and equivalents are believed to be within the spiritand scope of the invention as defined by the following claims.

What is claimed is:
 1. A carbonylation catalyst composition comprisingthe following and any reaction products thereof: an effective amount ofat least one Group 8, 9, or 10 metal source; an effective amount of acombination of inorganic co-catalysts comprising at least one Group 4metal source and at least one Group 11 metal source; and an effectiveamount of at least one salt co-catalyst with an anion selected from thegroup consisting of carboxylate, benzoate, acetate, sulfate, andnitrate; wherein the carbonylation catalyst composition is free of ahalide source.
 2. The carbonylation catalyst composition of claim 1,wherein the Group 8, 9, or 10 metal source is a palladium source.
 3. Thecarbonylation catalyst composition of claim 2, wherein the palladiumsource is palladium(II) 2,4-pentanedionate.
 4. The carbonylationcatalyst composition of claim 1, wherein the Group 4 metal sourcecomprises a titanium source and the Group 11 metal source comprises acopper source.
 5. The carbonylation catalyst composition of claim 4,wherein the titanium source is titanium(IV) oxide 2,4-pentanedionate andthe copper source is copper(II) 2,4-pentanedionate.
 6. The carbonylationcatalyst composition of claim 1, wherein the salt co-catalyst contains acation selected from the group consisting of alkali metal cation,alkaline-earth metal cation, guanidinium cation, and onium cation. 7.The carbonylation catalyst composition of claim 6, wherein the saltco-catalyst is at least one member selected from the group consisting ofalkylammonium carboxylate, alkali metal acetate, alkylammonium sulfate,and alkali metal nitrate.
 8. The carbonylation catalyst composition ofclaim 7, wherein the salt co-catalyst is at least one member selectedfrom the group consisting of tetrabutylammonium benzoate, sodiumacetate, tetrabutylammonium sulfate, and sodium nitrate.
 9. Thecarbonylation catalyst composition of claim 2, wherein the molar ratioof the Group 4 metal source to palladium is between about 0.1 to about100 and the molar ratio of the Group 11 metal source to palladium isbetween about 0.1 to about
 100. 10. The carbonylation catalystcomposition of claim 2, wherein the molar ratio of the salt co-catalystto palladium is between about 0.1 to about
 10000. 11. The carbonylationcatalyst composition of claim 1 further comprising at least oneactivating organic solvent.
 12. The carbonylation catalyst compositionof claim 11, wherein the activating organic solvent is at least onemember selected from the group consisting of polyether, nitrile,carboxylic acid amide, and sulfone.
 13. The carbonylation catalystcomposition of claim 1, further comprising at least one base.
 14. Thecarbonylation catalyst composition of claim 13, wherein the base is atleast one member selected from the group consisting of basic oxide,hydroxide, alkoxide, aryloxide, and amine.
 15. The carbonylationcatalyst composition of claim 14, wherein the base is one memberselected from the group consisting of alkali metal hydroxide,alkaline-earth metal hydroxide, and guanidinium hydroxide.
 16. Thecarbonylation catalyst composition of claim 15, wherein the basecomprises sodium hydroxide.
 17. The carbonylation catalyst compositionof claim 14, wherein the base comprises an onium hydroxide.
 18. Thecarbonylation catalyst composition of claim 17, wherein the basecomprises a tetraalkylammonium hydroxide.
 19. The carbonylation catalystcomposition of claim 17, wherein the base comprises tetramethylammoniumhydroxide.
 20. The carbonylation catalyst composition of claim 13,wherein the molar ratio of the base to the Group 8, 9 or 10 metal sourceis between about 0.1 to about
 1000. 21. A carbonylation catalystcomposition comprising the following and any reaction products thereof:an effective amount of palladium(II) 2,4-pentanedionate; an effectiveamount of a combination of titanium(IV) oxide 2,4-pentanedionate andcopper(II) 2,4-pentanedionate; and an effective amount of at least onesalt co-catalyst selected from the group consisting of sodium acetate,tetrabutylammonium benzoate, tetrabutylammonium sulfate,tetrabutylammonium nitrate, and sodium nitrate; wherein thecarbonylation catalyst composition is free of a halide source.
 22. Acarbonylation catalyst composition comprising the following and anyreaction products thereof: an effective amount of palladium(II)2,4-pentanedionate; an effective amount of a combination of titanium(IV)oxide 2,4-pentanedionate and copper(II) 2,4-pentanedionate; an effectiveamount of at least one salt co-catalyst selected from the groupconsisting of sodium acetate, tetrabutylammonium benzoate,tetrabutylammonium sulfate, tetrabutylammonium nitrate, and sodiumnitrate; and an effective amount of sodium hydroxide; wherein thecarbonylation catalyst composition is free of a halide source.
 23. Acarbonylation catalyst composition comprising the following and anyreaction products thereof: an effective amount of palladium(II)2,4-pentanedionate; an effective amount of a combination of titanium(IV)oxide 2,4-pentanedionate and copper(II) 2,4-pentanedionate; an effectiveamount of at least one salt co-catalyst selected from the groupconsisting of sodium acetate, tetrabutylammonium benzoate,tetrabutylammonium sulfate, and sodium nitrate; an effective amount ofsodium hydroxide; and an effective amount of tetraglyme; wherein thecarbonylation catalyst composition is free of a halide source. 24.Method for carbonylating an aromatic hydroxy compound, comprising thestep of contacting at least one aromatic hydroxy compound with oxygenand carbon monoxide in the presence of a carbonylation catalystcomposition comprising the following and any reaction products thereof:an effective amount of at least one Group 8, 9, or 10 metal source; aneffective amount of a combination of inorganic co-catalysts comprisingat least one Group 4 metal source and at least one Group 11 metalsource; and an effective amount of at least one salt co-catalyst with ananion selected from the group consisting of carboxylate, benzoate,acetate, sulfate, and nitrate; wherein the carbonylation catalystcomposition is free of a halide source.
 25. The method of claim 24,wherein the Group 8, 9, or 10 metal source is a palladium source. 26.The method of claim 25, wherein the palladium source is palladium(II)2,4-pentanedionate.
 27. The method of claim 24, wherein the aromatichydroxy compound is phenol.
 28. The method of claim 24, wherein theGroup 4 metal source comprises a titanium source and the Group 11 metalsource comprises a copper source.
 29. The method of claim 28, whereinthe titanium source is titanium(IV) oxide 2,4-pentanedionate and thecopper source is copper(II) 2,4-pentanedionate.
 30. The method of claim24, wherein the salt co-catalyst contains a cation selected from thegroup consisting of alkali metal cation, alkaline-earth metal cation,guanidinium cation, and onium cation.
 31. The method of claim 30,wherein the salt co-catalyst is at least one member selected from thegroup consisting of alkylammonium carboxylates, alkali metal acetates,alkylammonium sulfates, and alkali metal nitrates.
 32. The method ofclaim 31, wherein the salt co-catalyst is at least one member selectedfrom the group consisting of sodium acetate, tetrabutylammoniumbenzoate, tetrabutylammonium sulfate, and sodium nitrate.
 33. Thecarbonylation catalyst composition of claim 25, wherein the molar ratioof the Group 4 metal source to palladium is between about 0.1 mole toabout 100 moles per mole of palladium and the molar ratio of the Group11 metal source to palladium is between about 0.1 mole to about 100moles.
 34. The carbonylation catalyst composition of claim 25, whereinthe molar ratio of the salt co-catalyst to palladium is between about0.1 mole to about 10000 moles per mole of palladium.
 35. The method ofclaim 24, further comprising at least one activating organic solvent.36. The method of claim 35, wherein the activating organic solvent isone member selected from the group consisting of polyether, nitrile,carboxylic acid amide, and sulfone.
 37. The method of claim 24, furthercomprising at least one base.
 38. The method of claim 37, wherein thebase is at least one member selected from the group consisting of basicoxide, hydroxide, alkoxide, aryloxide, and amine.
 39. The method ofclaim 38, wherein the base comprises one member selected from the groupconsisting of alkali metal hydroxide, alkaline-earth metal hydroxide,and guanidinium hydroxide.
 40. The method of claim 39, wherein the basecomprises sodium hydroxide.
 41. The method of claim 38, wherein the basecomprises an onium hydroxide.
 42. The method of claim 41, wherein thebase comprises a tetraalkylammonium hydroxide.
 43. The method of claim42, wherein the base comprises tetramethylammonium hydroxide.
 44. Themethod of claim 37, wherein the molar ratio of the base to the Group 8,9 or 10 metal source is between about 0.1 to about
 1000. 45. A methodfor carbonylating an aromatic hydroxy compound, comprising the step ofcontacting at least one aromatic hydroxy compound with oxygen and carbonmonoxide in the presence of a carbonylation catalyst compositioncomprising the following and any reaction products thereof: an effectiveamount of palladium(II) 2,4-pentanedionate; an effective amount of acombination of titanium(IV) oxide 2,4-pentanedionate and copper(II)2,4-pentanedionate; and an effective amount of at least one saltco-catalyst selected from the group consisting of sodium acetate,tetrabutylammonium benzoate, tetrabutylammonium sulfate,tetrabutylammonium nitrate, and sodium nitrate; wherein thecarbonylation catalyst composition is free of a halide source.
 46. Amethod for carbonylating an aromatic hydroxy compound, comprising thestep of contacting at least one aromatic hydroxy compound with oxygenand carbon monoxide in the presence of a carbonylation catalystcomposition comprising the following and any reaction products thereof:an effective amount of palladium(II) 2,4-pentanedionate; an effectiveamount of a combination of titanium(IV) oxide 2,4-pentanedionate andcopper(II) 2,4-pentanedionate; an effective amount of at least one saltco-catalyst selected from the group consisting of sodium acetate,tetrabutylammonium benzoate, tetrabutylammonium sulfate, and sodiumnitrate; and an effective amount of sodium hydroxide; wherein thecarbonylation catalyst composition is free of a halide source.
 47. Amethod for carbonylating an aromatic hydroxy compound, comprising thestep of contacting at least one aromatic hydroxy compound with oxygenand carbon monoxide in the presence of a carbonylation catalystcomposition comprising the following and any reaction products thereof:an effective amount of palladium(II) 2,4-pentanedionate; an effectiveamount of a combination of titanium(IV) oxide 2,4-pentanedionate andcopper(II) 2,4-pentanedionate; an effective amount of at least one saltco-catalyst selected from the group consisting of sodium acetate,tetrabutylammonium benzoate, tetrabutylammonium sulfate, and sodiumnitrate; an effective amount of sodium hydroxide; and an effectiveamount of tetraglyme; wherein the carbonylation catalyst composition isfree of a halide source.